INDIAN HEAD PARK, Ill. (CBS) — Police have received hundreds of tips in the stabbing death of a 14-year-old girl at her southwest suburban home, but still have few clues about who killed her.

As CBS 2’s Roseanne Tellez reports, Kelli O’Laughlin was killed last Thursday in her family’s Indian Head Park home when she apparently walked in on a burglar.

Police issued a new call for help in finding Kelli’s killer on Tuesday, while also announcing the reward has increased to $60,000 for information leading to the arrest and conviction of whoever killed her.

It was the first murder that’s ever occurred in the southwest suburb and police wanted to reach out of Indian Head Park to anyone who might now something about the case.

Indian Head Park Police Chief Frank Alonzo said detectives from the Cook County Sheriff’s Police and the South Suburban Major Crimes Task Force have checked more than 100 leads, but said all appear to be dead ends.

“We’re following tips all over the city of Chicago and suburbs, whatever it takes,” Alonzo said. “We’re asking for support from people even outside the area.”

Alonzo refused to say if detectives believe that Kelli encountered someone she knew burglarizing her home and said detectives still believe that several rare, limited edition coins were the only items taken. The attacker apparently forced his way into the home from the rear.

“We’re still asking pawn shops, cash for gold … anybody that knows or heard about these coins to give us a call,” Alonzo said.

Expert Joe Rizdy, who owns a coin and stamp shop in LaGrange, told CBS 2’s Kristyn Hartman that the Sacagawea dollar coins police put on police flyers about Kelli’s murder wouldn’t raise a red flag, “because these are very common and still used today as currency.”

But if someone tried to pawn a brass and silver gaming token for the $22 it’s worth, that’s a little more unusual.

Rizdy’s store had several of them before Kelli’s murder. One of them had the word Flamingo, like the coin described in a police flyer about Kelli’s murder.

Rizdy said if he got a coin like that in his shop, he’d call police.

“At this time, I would, because that’s what they’re looking for,” he said.

Despite all the tips and the release of a sketch of a person seen in the area at the time of the crime, police said the investigation is stalled, with no arrests or suspects so far.

Still, sources said that Kelli’s family met with members of the South Suburban Major Crimes Task Force on Tuesday, to thank them for their efforts.

Alonzo said investigators are determined to find the killer.

“They have children and this just is, this is a – and I want to stress this – a 14-year-old defenseless little girl that didn’t deserve to die in her home,” Alonzo said.

At Kelli’s school, Lyons Township High School South, classmates wore purple, one of Kelli’s favorite colors, in remembrance of her on Tuesday.

Students said even other schools were showing support by wearing Lyons Township High School’s colors.